MOBNI6: TCS Ni-alloys Mobility Database

The TCS Ni-alloys Mobility Database (MOBNI) is a kinetic database containing mobility data for Ni-based alloys presented in a format suitable for simulation of diffusion controlled phenomena using the add-on Diffusion Module (DICTRA) and/or Precipitation Module (TC-PRISMA) as well as a few specific calculation types, such as Scheil with back diffusion.

MOBNI6 is compatible and primarily recommended for use in combination with the TCNI13 TCS Ni-based Superalloys thermodynamic database.

MOBNI: TCS Nickel Mobility Database Revision History. The current version of the database is MOBNI6.

Included Elements

There are 29 elements included in the most recent version of the database.

Al	B	C	Ca	Co	Cr	Cu	Fe	Hf	Mg
Mn	Mo	N	Nb	Ni	O	P	Pd	Pt	Re
Ru	S	Si	Ta	Ti	V	W	Y	Zr

Included Phases

FCC_A1 (γ )	FCC_L12 (γ´)	BCC_A2 (α)
BCC_B2 (β)	LIQUID	IONIC_LIQ

The phases have diffusion data included in the database. You can include other phases in a diffusion simulation. However, these other phases are treated as so-called diffusion NONE, i.e. there is no diffusion considered in these other phases. Any phase not listed above is automatically entered as diffusion NONE (in Console Mode in the DICTRA module or in Graphical Mode with the Diffusion Module (DICTRA) and/or Precipitation Module (TC-PRISMA)), as long as a thermodynamic description for the phases is retrieved prior to reading data from the mobility database.

Assessed Systems

FCC_A1

The database contains assessed impurity diffusion data in Ni for all included elements. It also includes complete and critical assessments for FCC_A1 in the following binary and ternary systems.

Binary

FCC_A1 Binary Assessed Systems
Al-B	Al-Cr	Al-Fe	Al-Ni	Al-Pt	Al-Ru	B-Ni	C-Cr	C-Fe	C-Ni
Co-Fe	Co-Mn	Co-Ni	Co-Pd	Co-Pt	Co-Re	Cr-Fe	Cr-Ni	Cu-Mn	Cu-Ni
Cu-Si	Fe-Ni	Fe-Pd	Fe-Pt	Hf-Ni	Mo-Ni	Mn-Ni	Nb-Ni	Ni-O	Ni-Pd
Ni-Pt	Ni-Re	Ni-Ru	Ni-Si	Ni-Ta	Ni-Ti	Ni-V	Ni-W	Ni-Y	Ni-Zr

Ternary

FCC_A1 Ternary Assessed Systems
Al-B-Ni	Al-Cr-Ni	Al-Mn-Ni	Al-Ni-Pt	Al-Ni-Ti	C-Cr-Fe	C-Cr-Ni	C-Fe-Ni
Co-Cr-Mo	Co-Cr-W	Co-Fe-Ni	Co-Mo-W	Co-Ti-V	Co-V-W	Cr-Fe-Ni	Cu-Mn-Ni
Cu-Ni-Si	Ni-Al-Co	Ni-Al-Nb	Ni-Al-Ta	Ni-Al-W	Ni-Co-Cr	Ni-Co-Mo	Ni-Co-Re
Ni-Co-Ru	Ni-Co-W	Ni-Cr-Mo	Ni-Cr-Nb	Ni-Cr-Pt	Ni-Cr-V	Ni-Cu-Cr	Ni-Cu-Mo
Ni-Cu-Ti	Ni-Fe-Ti	Ni-Fe-V	Ni-Mo-Ta	Ni-Mo-W	Ni-Ti-Cr

Quaternary

FCC_A1 Quaternary Assessed System
C-Cr-Fe-Ni

FCC_L12

Besides the Al-Ni system itself, the diffusion of the elements listed below in Ni₃Al have been optimized and validated against experimental data. For the remaining elements some estimates based on judgment are made.

FCC_L12
B	Co	Cr	Fe	Hf	Mn	Mo	Nb	Pd	Pt
Re	Ru	Si	Ta	Ti	V	W

BCC_A2

This phase does normally not appear in Ni-base superalloys, at least not in any larger quantities. Even so, there is a need for a description of this phase in order to successfully model the mobilities in the ordered bcc phase. The description for this phase is based on the description available in the MOBFE database.

BCC_B2

For this phase several of the binary systems in which this phase is present are optimized, e.g.

Al-Co

Al-Fe

Al-Ni

Co-Fe

Co-Ti

Ni-Ti

In addition, the diffusion of the following third elements in NiAl was studied and assessed. For the remaining elements some estimates based on judgment are made.

LIQUID

The description for the liquid is based on an assessment of the ternary Al-Fe-Ni system. In addition diffusivities for Mo, Re and W diffusion in Ni are optimized. The diffusivities of Ca, Mg and S are estimated using the modified Sutherland equation, whereas remaining elements due to lack of consistent data is expected to diffuse like Ni.

Limits

As in the spirit of the CALPHAD method, predictions can be made for multicomponent systems by extrapolation into multicomponent space of data critically evaluated and assessed based on binary, ternary and in some cases higher order systems. However, critical calculations must always be verified by equilibrium experimental data; it is the user's responsibility to verify the calculations but Thermo‑Calc Software AB is interested to know about any significant deviations in order to improve any future release.

The CALPHAD Method

The Thermo‑Calc databases are developed with the CALPHAD approach based on various types of experimental data and theoretical values (e.g. those from first-principles calculations). It is based on the critical evaluation of binary, ternary, and for some databases, important higher order systems. This enables predictions to be made for multicomponent systems and alloys of industrial importance. Among these, the thermodynamic database is of fundamental importance.

The CALPHAD Method and the Thermo‑Calc Databases. Also visit the video tutorials on our website or our YouTube playlist.

Additional Resources

Go to the Nickel-based Superalloys Databases page on our website where you can access this Technical Information plus learn more about the compatible thermodynamic database and its Validation and Calculation Examples Collection. Also explore further applications of Thermo‑Calc to nickel including links to resources such as examples, publications, and more.